Stabilizer fin



United States Patent James E. Radford Silver Spring, Maryland [21] Appl. No. 760,402

[22] Filed Sept. 18, 1968 [45] Patented Dec. 1, 1970 [73] Assignee The United States of America as represented by the Secretary of the Navy [72] Inventor [54] STABILIZER FIN 5 Claims, 6 Drawing Figs.

[52] U.S. Cl 102/10 [51] Int. CL... F42b 22/10 [50] Field 01 Search 102/10-18 [56] References Cited UNITED STATES PATENTS 2,786,414 3/1957 Wall 102/13 Primary Examiner- Verlin R. Pendegrass Attorneys-J. P. Dunlavey, J. O. Tresansky and JJC. Goldstein ABSTRACT: A moored marine mine having a nonmetallic, inflatable stabilizing fin with a plurality of fluidly sealed compartments, each of which is inflated with sea water, gas or a mixture thereof to a pressure of desirably at least 2-3 p.s.i. higher than the environmental hydrestatic pressure. A plurality of internal struts are secured to opposite side walls of the fin to maintain the fin in its desired shaped.

Patented Dec. 1, 1970 Sheet &

James E. Redford INVENTOR ATTORNEYS STABILIZER FIN BACKGROUND OF THE INVENTION This invention relates generally to stabilizing apparatus, and more particularly to a stabilizing fin for a marine device.

Those concerned with the development of marine devices have long recognized the need for stabilizing apparatus, particularly due to vortex shedding as the water current flows by the devices. Many marine devices may be stabilized by any convenient technique, such as appropriately shaping and weighting the particular device to provide the requisite trim and buoyancy. However, a variety of specialized marine devices, particularly military oriented marine devices, have unique limitations on the stabilization apparatus utilized because of the deployment technique and the mode of operation. For example, a number of military oriented marine devices, such as rockets, torpedoes, and mines, are discharged through the conventional torpedo tubes of the deploying craft, which may be a submarine. In such a situation, a generally cylindrical shape, at least at the time of discharge, is a fundamental prerequisite of the marine device. The prior art has contemplated the use of pivotally mounted, rigid, metal, popout fins, or wings, to solve this problem. But, as in practically all military devices, space and weight are an ever important tactical aspect to ensure the greatest payload delivery capability. Hence, the compartment required to house the prior art pop-out fins, or wings, materially reduces the space available for explosive payload, propulsion apparatus, and electronic instrumentation; and the fin or wing design significantly increases the bulk weight of the marine device. Still further, particularly in the case of moored mines, for example, the protruding metallic surface provided by the pop-out fins or wings may produce serious interference with the ultra sensitive acoustic listening systems incorporated within the marine device. Moreover, such a protruding fin or wing results in a sizeably larger rigid, metallic surface which produces a greater noise in addition to providing increased acoustic reflection, each of which makes the marine device appreciably more susceptible to enemy detection.

SUMMARY OF THE INVENTION Accordingly, one object of this invention is to provide new and improved stabilizing apparatus.

Another object of the'invention is the provision of a new and improved stabilizing fin for a marine device.

A further object of the instant invention is to provide a new and improved stabilizing fin for a marine device, which may be stored without adversely affecting the optimum contour of the marine device.

Still another object of the present invention is to provide a new and improved stabilizing fin for a marine device, characterized by light weightand small storage size.

A still further object of this invention is the provision of a new and improved stabilizing fin for a torpedo tube launched marine device, which enables a great payload delivery capability.

Another still further object of the instant invention is the provision of a new and improved stabilizing fin for a marine device, which produces a minimum of acoustical interference and detection susceptibility.

Briefly, in accordance with one embodiment of this invention, these and other objects are attained by providing, in a marine device, a fluid inflatable fin, fabricated of a relatively fluid impervious, rubbery material, which may be stored in a collapsed condition and inflated at a predetermined time or in response to a predetermined condition. The fin may include a plurality of separate, fluidly sealed compartments to aid in the maintenance of the desired trim and buoyancy and to enable the fin to function in the event of a leak in a localized portion thereof.

BRIEF DESCRIPTION OF THE DRAWINGS A more complete appreciation of the invention and many of the attendant advantages thereof will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a plan view ofthe marine device and fin according the present invention in its collapsed, or storage, condition;

FIG. 2 is a plan view, partly in section, of the marine device and fin according to the present invention in its expanded, or inflated, condition;

FIG. 3 is an elevation view ofthe apparatus shown in FIG. 2;

FIG. 4 is a perspective view of a portion of the fin of the present invention according to the preferred embodiment;

FIG. 5 is a schematic view ofa typical fluid inflating system according to the present invention and FIG. 6 is a perspective view of a moored mine and expanded, inflatable fin according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings wherein like reference characters designate identical or corresponding parts throughout the several views, and more particularly to FIGS. l-3 and 6 thereof wherein the marine device and stabilizing fin therefor of the present invention, indicated generally by reference numeral 10, is shown as consisting essentially of a marine device, such as a generally cylindrical marine mine 12,

moored by an anchor 13, and a fluid inflatable fin 14.

When fin 14 is in its collapsed, or storage, condition, as illustrated in FIG. 1, the fin is folded into a well 16 provided in mine housing 18 and is retained therein by a fairing section 20, which is releasably secured to the mine housing by any conventional means, such as explosive bolts (not shown). During storage, handling, launching, and planting, the mine fairing section 20 is secured to housing 18, and fin 14 is retained in well 16 in the collapsed condition. The mine planting is performed in the conventional manner until the mine reaches the mooring depth at which point (I) the fairing section is released in a conventional manner, such as explosively, electromechanically, internal pressure, or otherwise, and (2) the fin inflating process is begun.

Referring to FIGS. 2 and 3, in which fin 14 is illustrated in its expanded or inflated, condition, the fin is shown as being divided into a plurality of sections 22, fluidly sealed and isolated from one another by a plurality of solid section ribs 24 which may be fabricated from the same material as the remainder of the fin. A plurality of fin struts 26 are secured to opposing sidewalls 28 and 30 of the fin to prevent the fin from ballooning out of shape as the pressure therewithin is increased. Although side walls 28 and 30 are shown herein as tapering inward, it should be understood that they may be constructed parallel to one another to form a generally flat fin.

As illustrated in FIG. 4, the fin may be constructed of a fiber-woven fabric 32 in which a plurality of fibers 34 are cross-woven from one sidewall to the other. In such a situation, the struts 26, as illustrated in FIGS. 2 and 3, are an in tegral part of the sidewall fabric. Such an integrally woven product is conventional and is manufactured and sold by The Goodyear Company. The particular fiber to be used may be uncoated Rayon, rubber coated Rayon, Nylon, or the like. Although the integrally woven fabric fin, as illustrated in FIG. 4, is preferred, it should be understood that a variety of thin sheet materials, such as rubber, plastic, or other synthetic materials may be used, so'long as the material selected is fluid impervious and highly flexible so that the fin may be tightly collapsed.

It has been found that, in use, the fin should be inflated to a pressure at least 2-3 p.s;i. higher than the ambient hydrostatic pressure in order to provide a sufficiently rigid fin, and a simple, conventional hydrostat may be used to control this pressure. Referring now to FIG. 5, a fluid inflating system is illustrated. The inflating fluid is supplied to a fin section 22 through a conventional control valve 36. The control valve is responsive to a-c'onventional comparator 38 which receives a pair of signals generated from a conventional hydrostatic pressure transducer 40 and a conventional fin section pressure transducer 42. The comparator is designed to open valve 38 to admit fluid if the differential pressure is less than 2-3 p.s.i. Although the 23 p.s.i. appears to be the minimum satisfactory differential pressure, it should be understood that a greater pressure may be used so long as it is not so great as to rupture the fin section. Fluid pressure is applied to valve 38 by a pressure generating device 44 which may be a conventional compressed gas cylinder, if the inflating fluid is a gas, or a conventional pump connected to the ambient sea water by a conduit 46, if the inflating fluid is to be liquid sea water. It should be understood that either sea gas or liquid may be used to provide sufficient rigidity of the fin but that trim and buoyancy requirements may necessitate alternating the sections, some gas filled and some air filled. Alternatively, by conventional valving, each section could be filled with part gas and part water, if desired.

For handling and during mine planting operations, fin 14 is in the tightly collapsed storage position. As such the fin occupies a minimum amount of space, thusly providing great payload space, and enables the mine to be discharged through a conventional torpedo tube. Upon reaching the desired mooring depth, fairing section 20 is released, and the fin is inflated, using sea water, gas, or both. Once inflated to a differential pressure of at least 2-3 p.s.i., the tin is sufficiently rigid to provide the requisite stability to the mine. Since the inflated fin is fabricated of rubber or some synthetic material without any metal, the fin does not produce any significant amount of acoustical interference and does not render the mine noticeably more susceptible to detection.

Obviously, numerous modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

lclaim:

1. In combination with a generally cylindrical marine device, the improvement comprising:

a fluid inflatable stabilizing fin extending radially from said marine device, said fin having two sidewalls;

a plurality of struts secured at each extremity thereof to each of said sidewalls; and

means for applying to said fin a fluid pressure at least higher than the environmental hydrostatic pressure.

2. The improvement of claim 1 wherein said fin comprises a plurality of ribs secured at each extremity thereof to each of said sidewalls, thereby forming a plurality of sections fluidly sealed and isolated from one another.

3. The improvement of claim 1 wherein said fin is fabricated from a flexible, thin, nonmetallic, sheet material.

4. The improvement of claim 3 wherein said sheet material is a fiber-woven fabric.

5. The improvement of claim 4 wherein said fabric is woven from a rubber coated Rayon fiber. 

